Inventive concepts relate to an image sensor, and more particularly, to an image sensor which improves charge transfer efficiency.
A pixel array comprising a complementary metal-oxide semiconductor (CMOS) image sensor (CIS) may include a photoelectric conversion device in each pixel. The photoelectric conversion device may generate an electric signal. The electric signal may vary according to an amount of incident light and the CIS may generate an image by processing the electric signal.
As the demand for a high-definition image has recently increased, a pixel comprising a CMOS image sensor is desired to be miniaturized. However, charge transfer efficiency of a device included in a miniaturized pixel is reduced and accordingly, image quality may degrade. Thus, improvement is desired.